Most people are unaware of the type of shut off valves in their home but even though the difference between the two can be easy to identify, the performance of the two can be vastly different. Almost all residential shut off valves can be classified into two categories; gate valves and ball valves. A gate valve is an older “twist style” valve that consists of a round or oval handle that has to be turned multiple times to fully open or close the “gate” in the valve, which stops the flow of water (or is supposed to!). A ball valve can easily identified by a lever handle and involves only a 90 degree turn to open or close the valve body.
The ball valve gets its name from the internal construction of the valve itself. The lever is attached to a stainless-steel ball on the inside of the valve. The ball has a hole drilled through it and when the valve is on, the water passes through the hole portion, when the lever is turned 90 degrees, the ball turns to the solid side and it closes off the flow of water.
A gate valve gets its name from the internal construction as well because the gate raises and lowers to open or close the flow of water. The handle sits on a threaded stem that screws in and out as the gate raises and lowers. At the end of the gate is a washer that is used to seal off the flow of water when the gate is fully in the closed position.
Which is best?
Ball valves are much more reliable than gate valves for many reasons, mainly due to the reliability of the valve in an emergency situation. The washers in the gate valves eventually wear out and the stems become brittle, both of which create a multitude of issues. When the washer wears out, the flow of water is no longer shut off, deeming the valve essentially ineffective. In many cases, when you shut the gate off, the brittle stem will snap or break and the valve will be stuck in the closed position and will need to be replaced before services can be restored.
What type do I have?
The easiest way to identify the type of valve you have can be as simple as looking at the handle, is it a lever or a circle? Every shut off valve in your home is either a gate or ball valve and many homes have a mixture of both. If there is any twisting involved, you likely have a gate valve, if it’s just a 90 degree turn to open and close the valve, it’s a ball valve. The bottom line is that gate valves are not reliable and should never be trusted in an emergency situation. It is highly recommended that all valves in your home be converted over to ball valve style shut offs to give you peace of mind knowing that when you turn the valve off, its off!